The scraper chain conveyors used with preference is underground mining operations as face or gate conveyors have, as known, a conveying trough which is made up of individual conveyor pans which are interconnected by means of conveyor pan connections in a tensionally resistant manner while allowing limited vertical and horizontal movement. Numerous difference designs of the conveyor pans and their side profiles and also numerous designs of the conveyor pan connections are known.
In the case of the scraper chain conveyor which is known and has proven successful in practical mining operations, use is made of conveyor pans whose side profiles, serving for guiding the scrapers, respectively comprise two profiled strips which are welded to the conveying base lying in between (DE 40 06 183 A1, DE 41 28 512 A1, DE-U 295 02 953.6). In the case of these scraper chain conveyors, for the conveyor pan connections use is always make of toggle connections, the toggle pins of which are inserted in toggle pockets of the coupling plates which are welded in between the outwardly directed flange strips of the side profiles.
Among the numerous known conveyor pan connections, the prior art also includes those in which there are used as coupling elements chain link-like double shackles, which are fitted by their inner openings, divided by a cross-piece, onto coupling pins and are secured in the coupling position by means of releasable securing elements, which comprise, for example, two-pronged forks which can be inserted into bores of retaining lugs. In the case of these long-known conveyor pan connections, the coupling parts are arranged on the outside, either directly on the side profiles of the conveyor pans or else on attachments, for example guide bars, which are screwed on the side profiles of the conveyor pans (DE 21 53 181 C2, DE 29 04 525 C2).